Once she’d graduated from college, landed a job and married her boyfriend, Ms. Cortese found herself turning to her grandmother for counsel on everything from dealing with in-laws and buying a house to throwing dinner together when she came home from work.

“She gave me the feeling that whatever I did was O.K.: ‘You’ll get through it. Not everything has to be perfect,’ ” said Ms. Cortese, now 38. “She had the wisdom just from having lived so long. It was always comforting.”

Her grandmother, Ann Ciampa, occasionally needs her help, too. Though still healthy and independent at 90, Mrs. Ciampa asks her granddaughter to buy her health food supplies online. She stayed with Ms. Cortese, who now lives in nearby Linden, when hurricanes caused extended power failures in the area, and she relied on her granddaughter for a ride home after cataract surgery. (She gives “gas money,” too, which Ms. Cortese accepts with a certain amount of private eye-rolling.)

The cycle continues. Ms. Cortese hosted her grandmother’s 90th birthday celebration last month. And now that she has two children, she still seeks Mrs. Ciampa’s advice. “Raising kids, when you never know what you’re doing, it’s nice to sit back and hear her say: ‘It’s fine. Don’t worry so much,’ ” she told me.

Much of the research on grandparents and grandchildren has focused on young children and on the safety-net function that grandparents can provide in troubled families. But lengthening lifespans mean that more people will have adult relationships with their grandparents, too, sometimes for many years.

“We know relatively little about what grandparents and grandchildren do for each other on a daily basis during the grandchildren’s adulthood,” said Sara Moorman, a Boston College sociologist who set out to learn more. She presented the results of her research at the American Sociological Association’s annual meeting in New York this week.

Using the Longitudinal Study of Generations, which surveys families in Southern California about every three years, Dr. Moorman and her co-investigator, Jeffrey Stokes, looked at data from 1985 through 2004. Their sample included 376 grandparents and 340 grandchildren (selected randomly if a grandparent had more than one grandchild) who were over the age of 16. In 1994, halfway through the period in question, the grandparents’ mean age was 77; the grandchildren’s was 31.

These relationships had impact, the results showed. When the pairs described themselves as fairly close emotionally (“affectual solidarity,” the sociologists called it), both generations showed fewer symptoms of depression on a standard psychological scale than those with more detached relationships. Those with close relationships were less likely to report feeling lonely or sad, and were not as prone to symptoms like insomnia, lack of energy or sleeplessness.

More practical assistance — for example, “helping each other with chores, with transportation, with advice, with money,” Dr. Moorman said — had no significant connection to grandchildren’s depression scores, but it did affect the grandparents’ scores. They reported fewer depressive symptoms if they provided help (“functional solidarity”) or if the assistance was reciprocal.

If they were only the recipients of aid, though, the grandparents’ depression scores were higher. “Older adults want to continue to be independent and productive,” Dr. Moorman said. “When they can’t give back, that’s depressing.”

It’s worth noting that, over all, these grandparents and grandchildren — some of whom may have moved away from each other over the years of the study — did not describe particularly high levels of involvement. Based on six questions and a scale in which 1 meant “not at all” close and 6 meant “extremely” close, the grandparents rated their emotional closeness at 3.96 on average; the grandchildren rated their relationships at 3.54. “Pretty centrist responses,” Dr. Moorman said.

Over the full study period, the grandparents estimated that they gave practical support to adult grandchildren about 14 percent of the time, received it about 3.4 percent of the time, and both gave and received it about 8 percent of the time. The grandchildren saw the relationship differently. “Grandparents say they’re giving more,” Dr. Moorman said. “The grandkids perceive more of an exchange.” Most of the time, though, both generations said they neither received nor provided practical support.

Still, the connections between these relationships and depression scores were statistically significant. “A close relationship that induces exchange is good for both parties,” Dr. Moorman said. “Grandchildren and grandparents are a resource for each other, or at least they can be.”

She knows whereof she speaks. “My grandma and I were really close,” she said. They lived in State College, Pa., where as a teenager, Dr. Moorman worked in the public library. Her grandmother, Mary Moorman, whose house was right next door, often made her lunch. And with her brand-new driver’s license, Dr. Moorman drove her to hairdressers’ appointments and restaurants, thrilled to be trusted.

Her grandmother died last summer at 94. The new study, Dr. Moorman said, was a tribute to her.

Paula Span is the author of “When the Time Comes: Families With Aging Parents Share Their Struggles and Solutions.”

Last modified: August 16, 2013
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